Backport PR pandas-dev#32444: CI: ax.rowNum and ax.colNum attributes deprecated in Matplotlib 3.2 (pandas-dev#32456)

Co-authored-by: Simon Hawkins <[email protected]>

Author: simonjayhawkins

pandas/plotting/_matplotlib/tools.py

@@ -9,6 +9,8 @@
 from pandas.core.dtypes.common import is_list_like
 from pandas.core.dtypes.generic import ABCDataFrame, ABCIndexClass, ABCSeries
 
+from pandas.plotting._matplotlib import compat
+
 
 def format_date_labels(ax, rot):
     # mini version of autofmt_xdate
@@ -288,20 +290,26 @@ def _remove_labels_from_axis(axis):
 
 def _handle_shared_axes(axarr, nplots, naxes, nrows, ncols, sharex, sharey):
     if nplots > 1:
+        if compat._mpl_ge_3_2_0():
+            row_num = lambda x: x.get_subplotspec().rowspan.start
+            col_num = lambda x: x.get_subplotspec().colspan.start
+        else:
+            row_num = lambda x: x.rowNum
+            col_num = lambda x: x.colNum
 
         if nrows > 1:
             try:
                 # first find out the ax layout,
                 # so that we can correctly handle 'gaps"
                 layout = np.zeros((nrows + 1, ncols + 1), dtype=np.bool)
                 for ax in axarr:
-                    layout[ax.rowNum, ax.colNum] = ax.get_visible()
+                    layout[row_num(ax), col_num(ax)] = ax.get_visible()
 
                 for ax in axarr:
                     # only the last row of subplots should get x labels -> all
                     # other off layout handles the case that the subplot is
                     # the last in the column, because below is no subplot/gap.
-                    if not layout[ax.rowNum + 1, ax.colNum]:
+                    if not layout[row_num(ax) + 1, col_num(ax)]:
                         continue
                     if sharex or len(ax.get_shared_x_axes().get_siblings(ax)) > 1:
                         _remove_labels_from_axis(ax.xaxis)